Stock market slumps after an early gain amid uncertainty over Trump’s trade war

The U.S. stock market is careening through a second straight day of stunning swings Tuesday as uncertainty reigns about what whether President Donald Trump will ease up on his trade war, which is scheduled to kick into a higher gear after midnight.

The S&P 500 lost an early gain of 4.1%, which had it on track for its best day in years, and slumped 1.7% with about an hour left in trading.

The Dow Jones Industrial Average lost 403 points, or 1%, after giving up its earlier surge of 1,460 points...